Remove some c_str() calls from StringCs in xfa docs.

fpdfsdk/fpdfxfa/include/fpdfxfa_doc.h

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #ifndef FPDFSDK_FPDFXFA_INCLUDE_FPDFXFA_DOC_H_
 #define FPDFSDK_FPDFXFA_INCLUDE_FPDFXFA_DOC_H_
 
 #include <vector>
@@ skipping 74 matching lines @@
 
   // host method
   virtual int32_t CountPages(CXFA_FFDoc* hDoc);
   virtual int32_t GetCurrentPage(CXFA_FFDoc* hDoc);
   virtual void SetCurrentPage(CXFA_FFDoc* hDoc, int32_t iCurPage);
   virtual FX_BOOL IsCalculationsEnabled(CXFA_FFDoc* hDoc);
   virtual void SetCalculationsEnabled(CXFA_FFDoc* hDoc, FX_BOOL bEnabled);
   virtual void GetTitle(CXFA_FFDoc* hDoc, CFX_WideString& wsTitle);
   virtual void SetTitle(CXFA_FFDoc* hDoc, const CFX_WideString& wsTitle);
   virtual void ExportData(CXFA_FFDoc* hDoc,
-                          const CFX_WideStringC& wsFilePath,
+                          const CFX_WideString& wsFilePath,
                           FX_BOOL bXDP = TRUE);
-  virtual void ImportData(CXFA_FFDoc* hDoc, const CFX_WideStringC& wsFilePath);
+  virtual void ImportData(CXFA_FFDoc* hDoc, const CFX_WideString& wsFilePath);
   virtual void GotoURL(CXFA_FFDoc* hDoc,
-                       const CFX_WideStringC& bsURL,
+                       const CFX_WideString& bsURL,
                        FX_BOOL bAppend = TRUE);
   virtual FX_BOOL IsValidationsEnabled(CXFA_FFDoc* hDoc);
   virtual void SetValidationsEnabled(CXFA_FFDoc* hDoc, FX_BOOL bEnabled);
   virtual void SetFocusWidget(CXFA_FFDoc* hDoc, CXFA_FFWidget* hWidget);
   virtual void Print(CXFA_FFDoc* hDoc,
                      int32_t nStartPage,
                      int32_t nEndPage,
                      uint32_t dwOptions);
 
   // LayoutPseudo method
@@ skipping 117 matching lines @@
   CXFA_FFDoc* m_pXFADoc;
   CXFA_FFDocView* m_pXFADocView;
   CPDFXFA_App* m_pApp;
   IJS_Context* m_pJSContext;
   CFX_ArrayTemplate<CPDFXFA_Page*> m_XFAPageList;
   LoadStatus m_nLoadStatus;
   int m_nPageCount;
 };
 
 #endif  // FPDFSDK_FPDFXFA_INCLUDE_FPDFXFA_DOC_H_